Name at least three muscles that actively contracts during the following activities and name its action and innervation:
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Turning a door knob
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Supinator
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Action: Assist to pronate and supinate the forearm.
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Innervation: Deep branch of the radial nerve.
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Pronator quadratus
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Action: Pronates forearm at radioulnar joints.
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Innervation: Median nerve.
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Pronator teres
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Action: Pronates forearm at radioulnar joints and weakly flexes forearm at elbow joint.
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Innervation: Median nerve.
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Throwing a baseball overhead
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Deltoid
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Action: Lateral fibers abduct arm at shoulder joint; anterior fibers flex and medially rotate arm at shoulder joint; posterior fibers extend and laterally rotate arm at shoulder joint.
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Innervation: Axillary nerve.
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Subscapularis
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Action: Medially rotates arm at shoulder joint.
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Innervation: Upper and lower subscapular nerve.
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Teres Major
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Action: Extends arm at shoulder joint and assists in adduction and medial rotation of arm at shoulder joint.
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Innervation: Lower subscapular nerve.
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Kicking a ball
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Quadriceps femoris & rectus femoris
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Action: All four heads extend leg at knee joint; rectus femoris muscle acting alone also flexes thigh at hip joint.
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Innervation: Femoral nerve.
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Iliopsoas
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Action: Psoas major and iliacus muscles acting together flex thigh at hip joint, rotate thigh laterally, and flex trunk on hip as in sitting up from supine position.
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Innervation: Lumbar spinal nerves L2–L3.
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Doing sit-ups
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Internal oblique
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Action: Acting together, compress abdomen and flex vertebral column; acting singly, laterally flex vertebral column, especially lumbar portion, and rotate vertebral column.
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Innervation: Thoracic spinal nerves T8–T12, the iliohypogastric nerve, and ilioinguinal nerve.
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Rectus abdominis
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Action: Flexes vertebral column, especially lumbar portion, and compresses abdomen.
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Innervation: Thoracic spinal nerves T7–T12.
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Transversus abdominis
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Action: Compresses abdomen.
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Innervation: Thoracic spinal nerves T8–T12, iliohypogastric nerve, and ilioinguinal nerve.
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Walking
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Quadriceps femoris
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Action: All four heads extend leg at knee joint; rectus femoris muscle acting alone also flexes thigh at hip joint.
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Innervation: Femoral nerve.
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Gluteus maximus
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Action: Extends thigh at hip joint and laterally rotates thigh; helps lock knee in extension.
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Innervation: Inferior gluteal nerve
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Gastrocnemius
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Action: Plantar flexes foot at ankle joint and flexes leg at knee joint.
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Innervation: Tibial nerve.
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Breathing
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Diaphragm
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Action: Contraction of diaphragm causes it to flatten and increases vertical dimension of thoracic cavity, resulting in inhalation; relaxation of diaphragm causes it to move superiorly and decreases vertical dimension of thoracic cavity, resulting in exhalation.
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Innervation: Phrenic nerve, which contains axons from cervical spinal nerves (C3–C5).
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Internal intercostals
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Action: Contraction draws adjacent ribs together to further decrease anteroposterior and lateral dimensions of thoracic cavity during forced exhalation.
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Innervation: Thoracic spinal nerves T2–T12.
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External intercostals
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Action: Contraction elevates ribs and increases anteroposterior and lateral dimensions of thoracic cavity, resulting in inhalation; relaxation depresses ribs and decreases anteroposterior and lateral dimensions of thoracic cavity, resulting in exhalation.
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Innervation: Thoracic spinal nerves T2–T12.
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REFERENCE:
Tortora, Gerard, and Bryan Derrickson. Principles of Anatomy and Physiology. 15th ed., Wiley, 2016.